Optimizing Zigbee long range communications systems

本可行性研究项目（随后实施）涉及ZigBee无线网络和底层基础设施的优化，旨在最大限度地降低成本，同时最大限度地提高最终用户的可靠性和通信范围。该项目侧重于设计和验证更有效的现场可编程门阵列（FPGA）平台，该平台将允许在网络中合并更少的节点，同时保持良好的覆盖范围、服务质量（QOS）和满足最大延迟需求。该方法包括网格拓扑的使用、物理层（PHY）中不同分集技术的应用（如空间复用、波束形成、形成多用户多输入多输出（MIMO）系统和空时编码）、媒体访问控制（MAC）层的智能天线技术实现。开发的产品（接入点或基站）将被命名为ZigBee远程（ZLR），它代表了建立在802.15.4物理芯片组之上的下一代自组织无线网络技术，而客户端设备既可以是ZLR，也可以是传统的ZigBee设备。该产品围绕FPGA构建，物理层作为外设实现，FPGA内的IP核实现，更高层协议作为嵌入式软件实现。因此，硬件和软件的相互设计是必要的，以实现所提议的产品的所有预期功能。

This feasibility study project (followed by implementation) is dealing with optimization of ZigBee wireless networks and underlying infrastructure, aiming on minimizing the cost while maximizing the reliability and communication ranges for the end user. This project focuses on the design and validation of more effective Field-Programmable Gate Array (FPGA) platform, which will allow incorporation of less nodes in the network, while maintaining, good coverage, Quality of Service (QOS) and satisfying the maximum latency demands. The methodology includes use of mesh topology, application of different diversity techniques in Physical Layer (PHY) (such as spatial multiplexing, beamforming, forming multiuser Multiple-Input Multiple-Output (MIMO) system and space-time coding), smart antennas technique implementation of Media Access Control (MAC) layer. The developed product (access point or the base station) will be named ZigBee Long Range (ZLR) and it represents a next generation self-organized wireless network technology built on top of 802.15.4 physical chipsets, while the client devices can be both ZLR or conventional ZigBee devices. The product is build around an FPGA while PHY layer is implemented as peripherals, IP cores within an FPGA and the higher layers protocols as an embedded software. Hence, mutual design of hardware and software is necessary in order to fulfil all desired functionality of the proposed product.